US4746804A
Expired / Lapsed
US
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Photosensitive pixel with exposed blocking element
Assignee: Nippon Steel Corp
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Filing: 1987-09-08
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Granted: 1988-05-24
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Expires: 2007-09-08
Abstract
Abstract By maintaining the first electrodes of a photogenerative element and a current blocking element at a common potential while electrically interconnecting the second electrodes thereof, the blocking element need not be masked from incident radiation because the stored electrical signal generated by the photogenerative element will not be dissipated by photogenerated carrier pairs contributed by the current blocking element.
Inventors
- 👤 Koichi Kitamura
- 👤 Louis D. Swartz
- 👤 Clive Catchpole
- 👤 Zvi Yaniv
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:52
CPC Classifications
H; H10; H10F; H10F39/00; H10F39/10; H10F39/12; H10F39/18; H04; H04N; H04N1/00; H04N1/40; H04N1/40056; H10D; H10D44/00; H10D44/40; H10D44/45; H10D44/452
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
126 words
A photoresponsive pixel for generating a signal indicative of the radiation emanating from an image-bearing surface, said pixel including: a photogenerative element formed of a given number of layers of semiconductor alloy material and providing a detectible signal corresponding to the quantity of radiation incident thereupon; at least one blocking element formed on the same number of layers of semiconductor alloy material as the photogenerative layer and electrically connected to the photogenerative element so as to selectively block the flow of current thereto; said blocking element including a photogenerative region at least partially unshielded from said incident radiation; and said photogenerative element and said blocking element closely spaced relative to one another so as to receive radiation from substantially the same portion of the image-bearing surface.
Claim 2
Dependent Claim
126 words
A photoresponsive pixel for generating a signal indicative of the radiation emanating from an image-bearing surface, said pixel including: a photogenerative element formed of a given number of layers of semiconductor alloy material and providing a detectible signal corresponding to the quantity of radiation incident thereupon; at least one blocking element formed on the same number of layers of semiconductor alloy material as the photogenerative layer and electrically connected to the photogenerative element so as to selectively block the flow of current thereto; said blocking element including a photogenerative region at least partially unshielded from said incident radiation; and said photogenerative element and said blocking element closely spaced relative to one another so as to receive radiation from substantially the same portion of the image-bearing surface.
Claim 3
Dependent Claim
13 words
An element as in claim 1, wherein said photogenerative element is a photoresistor.
Claim 4
Dependent Claim
13 words
An element as in claim 1, wherein said photogenerative element is a phototransistor.
Claim 5
Dependent Claim
13 words
An element as in claim 1, wherein said photogenerative element is a photodiode.
Claim 6
Dependent Claim
20 words
An element as in claim 4, wherein said photodiode includes oppositely doped layers formed of thin film semiconductor alloy material.
Claim 7
Dependent Claim
34 words
An element as in claim 5, wherein said photodiode further includes a layer formed of substantially intrinsic semiconductor alloy material interposed between said oppositely doped layers so as to form a p-i-n type photodiode.
Claim 8
Dependent Claim
45 words
An element as in claim 6, wherein at least one of the semiconductor layers of said p-i-n type photodiode is formed from a material chosen from the group consisting essentially of: amorphous silicon alloy materials, amorphous germanium alloy materials, and amorphous silicon: germanium alloy materials.
Claim 9
Dependent Claim
32 words
An element as in claim 1, wherein said blocking element includes a layer of photoresponsive semiconductor alloy material capable of generating charge carrier pairs in response to the absorption of incident radiation.
Claim 10
Dependent Claim
13 words
An element as in claim 1, wherein said blocking element is a transistor.
Claim 11
Dependent Claim
13 words
An element as in claim 1, wherein said blocking element is a diode.
Claim 12
Dependent Claim
22 words
An element as in claim 10, wherein said diode includes a pair of oppositely doped layers of thin film semiconductor alloy material.
Claim 13
Dependent Claim
31 words
An element as in claim 11, wherein said diode includes a layer of intrinsic semiconductor alloy material interposed between said oppositely doped layers so as to provide a p-i-n type diode.
Claim 14
Dependent Claim
40 words
An element as in claim 12, wherein said p-i-n type diode includes at least one layer of semiconductor alloy material chosen from the group consisting essentially of: amorphous silicon alloy materials, amorphous germanium alloy materials, and amorphous silicon:germanium alloy materials.
Claim 15
Dependent Claim
14 words
An element as in claim 10, wherein said diode is a Schottky barrier diode.
Claim 16
Dependent Claim
32 words
An element as in claim 1, further including means for maintaining the second electrode of the photogenerative element and the second electrode of the current blocking element at a substantially equal potential.
Claim 17
Dependent Claim
18 words
An element as in claim 15, wherein said potential maintaining means maintains a potential of approximately 0 volts.
Claim 18
Dependent Claim
17 words
An element as in claim 15, wherein said potential maintaining means includes a low impedance current amplifier.
Claim 19
Dependent Claim
100 words
An element as in claim 1, wherein said photogenerative element is a photodiode having an anode and a cathode; said blocking element is a blocking diode having an anode and cathode; the cathodes of the photodiode and the blocking diode are electrically interconnected by an electrical conductor so that upon exposure of the photodiode to radiation, an electrical signal in the form of photogenerated carrier pairs will be stored on said electrical conductor; and the anode of the photodiodes and the anode of the blocking diode are maintained at substantially similar electrical potentials while the circuit is exposed to radiation.
Claim 20
Dependent Claim
43 words
An element as in claim 18, further comprising a plurality of photodiodes and plurality of associated blocking diodes operatively disposed and arranged for use as an array of pixels, each pixel provides an electrical signal corresponding to the quantity of radiation incident thereupon.
Claim 21
Dependent Claim
13 words
An element as in claim 19, wherein said array of pixels is linear.
Claim 22
Dependent Claim
26 words
An element as in claim 18, wherein the relative surface areas of the blocking diode to the photodiode differs by a factor of at least 5.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-24 | 1991-11-23 | 1992-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-24 | 1995-11-23 | 1996-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-24 | 1999-11-23 | 2000-05-24 | $7700.00 | Window Closed / Lapsed |